increase required libosmocore version

osmo-remsim depends on a variety of modern libosmocore features,
and now that libosmocore 1.6.0 has been tagged, we can finally depend
on a more recent minimum version.

Change-Id: Ic3cb86b5be524f15d118bcb7ec1947608fbbb034
diff --git a/contrib/osmo-remsim.spec.in b/contrib/osmo-remsim.spec.in
index 90ef773..bfc5f36 100644
--- a/contrib/osmo-remsim.spec.in
+++ b/contrib/osmo-remsim.spec.in
@@ -31,7 +31,7 @@
 %endif
 BuildRequires:  pkgconfig(libasn1c) >= 0.9.30
 BuildRequires:  pkgconfig(libosmoabis)
-BuildRequires:  pkgconfig(libosmocore) >= 0.11.0
+BuildRequires:  pkgconfig(libosmocore) >= 1.6.0
 BuildRequires:  pkgconfig(libosmogsm) >= 0.11.0
 BuildRequires:  pkgconfig(libosmosim)
 BuildRequires:  pkgconfig(libpcsclite)